In an attempt to make read only memory (ROM) arrays more dense, read only memory cells capable of being programmed to more than the two states typical for a ROM have been developed. As a practical matter and for convenience such cells are normally chosen to have four possible states although some other number of states can be chosen. For example, U.S. Pat. No. 4,327,424 to Philip T. Wu describes a three state cell. There are two primary approaches to developing a more-than-two-state transistor cell for MOS technology ROMs. One approach is to vary threshold voltages for the differing states. Because the threshold voltage of an MOS transistor is determined by the concentration of dopant in the channel, each additional state beyond the normal two states requires not only an additional process step for doping the selected channels but an additional program mask for masking the dopant from the unselected channels as well. The second approach has a transistor cell with a gain selected from more than two possible gains. The gain is directly related to the width to length ratio of the gate of the transistor. One of either the length or width is varied to achieve the desired variation in gain. U.S. Pat. No. 4,272,830 to Jerry D. Moench describes such an approach. Advantages are that no additional programming steps are required, and the one necessary programming step is relatively late in the process. A disadvantage is that in order to obtain sufficient gain differential for reliable detection of the state of the cell, the cell must be relatively large to accommodate the potential gate dimensions because only one of the length and width is varied.